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Fenix TK70 with measurements and outdoor beamshots

Fenix TK70

Fenix was one of the first Chinese companies that made high quality flashlights and has a broad selection of lights, I have only reviewed a few of them: TK41, LD01, E05 and TK45. This time I look at the most powerful light Fenix has ever made the TK70. The light is also the largest light Fenix has ever made, it uses 3 leds and 4 D batteries. The light has four brightness settings and two flashing modes and uses the same interface as the TK35, TK41 and TK60 (more about that later). The light is made of aluminum with hard-anodized (Type 3) finish.

The light is delivered in a cardboard box with foam insert.

The box contains the light (head, 2xbody, tailcap), 3 extra o-rings, a lanyard, a shoulder strap, 3 caps for the head and battery tube, a manual and a warranty card. Note: The tube is in two parts, a 3 and a 1 D cell, they have to be used together because the light need 4 D cells to work.

The light has a triple smooth reflector with a 3 XM-L led at the bottom. The sides of the bezel has some plain faces, this work as a anti roll device.

As usual on high power lights it has some cooling fins and just behind the fins are the switches. One switch is on/off and with a double click it will change between normal and flashing modes. The other switch is used to select brightness (low-medium-high-turbo) or flashing mode (sos-strobe), press on it to change brightness or flashing mode. The last selection of this switch is remembered and the light will start at the same setting next time it is turned on. Note: The light never starts in flashing modes, always in steady brightness modes.

The battery connection in the head is recessed to provide mechanical polarity protection. There is a spring behind the center connection, i.e. the batteries will rest on the plastic ring with the body, not on the plus connection with the nipple.

The head uses square cut threads for connection to the body. There is also a o-ring to seal the connection from water.

The body is cut with large rectangles to improve the grip, except the extender part.

The tailcap is flat, i.e. the light can tail stand, but due to the length of the light it is not very safe. The tailcap has the usual spring for battery connection.

The light includes 3 caps that can be placed over the threads when the light is disassembled, but these caps does not have any type of lock and will only stay on if there is something external to hold them.

The light includes a lanyard and a shoulder strap, but I do not like the design. The strap is very thin and the light is missing a forward mounting point for the strap.

Here are some examples on how the shoulder strap can be mounted.

Here is all the part the light can be disassembled in without tools.

The TK70 is the brightest led light at the current time, it has not only a very high lumen output, but the 3 emitters are also focused very well, giving the light a good throw. I wonder why it has a two part body, when it can only work with 4 batteries and I do not like the shoulder strap, it is too thin and there is no mounting point on the head.
Looking at the price may explain the reason for the less than ideal solutions Fenix has used here, the light is cheap compared to other high power led lights, but it is the brightest of them.

Technical specification and measurements

This light is designed for 4xD NiMH batteries and can work on 4xD Alkaline or 3xD batteries, but only at the lower power settings.

In the above table I have collected all modes, measured at 4.8 volt. I have also included off as a mode, because the light uses a small amount of power. All the estimated runtimes are with 9000mAh D batteries. The estimated lumen is scale from the specified maximum. The brightness is a relative measurement from a lux meter.

A voltage sweep at high shows a very nice stabilization. When the voltage goes down the light will automatic change to a lower mode. The light has a very high current consumption and there is some noise from the driver when running in turbo mode.
When the light steps down in brightness it will change the selected brightness, i.e. even if the light is turned off it will next time turn on at the current reduced brightness level, the switch must be used to increase brightness again.

In high the light has perfect stabilization and uses considerable less current than in turbo.

Again perfect stabilization, the two dip in current at 3 and 3.3 volt is the low battery warning (The light meter was to slow to register it).

Low does also have perfect stabilization and does also show the battery warning.

The good stabilization and automatic step down can also be seen in the runtime. With the alkaline I used (Panasonic) the runtime on turbo was less than one minute and after 26 minutes it drops down to medium. All runtimes where done with 4 cells, the light could not use turbo or high with 3 cells for any length of time.

The light has a dual frequency strobe with 6.8 and 15.4 hz, it changes between them each 1.8 second.

The sos uses a 0,37 second dot and it takes 11.8 second to transmit, there is a 2.5 second pause before next sos.

The light is current regulated and there is only a small amount of high frequency noise in the light.

Comparison to other Flashlights

Olight SR90, Olight SR91, Olight SR92

Fenix TK41, Fenix TK60, Fenix TK70:

For the full comparison to other lights with graphs and beamshots see here

Re: Fenix TK70 with measurements and outdoor beamshots

Very nice review. I have to disagree on two points, though: The strap is not very wide, but really sufficient to transport the TK70. This light tailstands surprisingly good for the size, provided you have a fairly stable surface or don't move around too close to it, otherwise the sound of it falling can be deafening.

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by Cataract

Very nice review. I have to disagree on two points, though: The strap is not very wide, but really sufficient to transport the TK70. This light tailstands surprisingly good for the size, provided you have a fairly stable surface or don't move around too close to it, otherwise the sound of it falling can be deafening.

Yes, you can transport the light with the strap, but it is a low quality type of strap. Check the Olight SR90, SR91 and SR92 to see how to do it the right way. But there is a significant price difference between the TK70 and the Olight, the TK70 is cheapest and brightest.
I do like both the SR lights and the TK70, but not for the same reasons, TK70 wins on price and brightness, SR lights wins on quality and accessories.

Originally Posted by Cataract

I really like the multiple comparison beam shots.

I believe that the full beamshot with bar graphs and different beamshot locations is a very important part of the review, it provides a perspective on the light, how is it compared to other light on a couple of different parameters.

Re: Fenix TK70 with measurements and outdoor beamshots

Great Review. I just got my TK70 in yesterday. It was hard waiting for that darn Sun to go down so I could really see what this thing could do. Its like a 500 foot long light sabre. I had to be careful where I pointed it but indeed it lit up tree tops 2 streets over from were I live. People must have been thinking the police heli was investigating in the area.

I was looking for the best price from a known retailer and I found this on Shopwiseguys for $199 with free shipping and batteries (I tried calling Batt Junction for a price match but they declined)....looking today it went up ten bucks and the batteries (Ray o vac Alkaline PROs) are no longer included. Incidentaly the brand new alkilines will only hold the TK70 in Turbo for about 20 or 30 seconds. Once I put my Tenergy 10,000mah rechargeable cells in there I was good to go.

FYI as a self defense item: I enlisted the wife to take the light and shine it at me when I came in the door. MAN, if you were not expecting this beam, it would take your sight out for a good little while (long enough to Run, Draw, or Bonk them with this club of a light)

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by Everest29035

FYI as a self defense item: I enlisted the wife to take the light and shine it at me when I came in the door. MAN, if you were not expecting this beam, it would take your sight out for a good little while (long enough to Run, Draw, or Bonk them with this club of a light)

Enjoy the light everybody

I believe you could easily kill someone with one blow. Medieval maces did not even weigh half of that thing and could go through helmets... I'll certainly transport it inside my backpack when heading for my beamshot location after sunset.

Re: Fenix TK70 with measurements and outdoor beamshots

Another fantastic review, thanks HKJ.
I agree with you, the strap is crap. It's out of context with the rest of the light, like an afterthought.
Real shame. Other than that, an excellent performing light.

Re: Fenix TK70 with measurements and outdoor beamshots

Thanks for a great review!!

I still dont know...if i should buy this light vs the Olight. I like the fact that its BRIGHT and the price is right. But I also look at Quality. Is it justifiable to lose some quality and gain brightness?? and the price?? pls. response anyone.... im thinking of a big torch for my christmas gift.

Re: Fenix TK70 with measurements and outdoor beamshots

i had both but i returned the SR92 as I couldnt justify keeping both. SR92 is great but less bright. It was also WAY more expensive and as a result, i was afraid to use for fear of scratching it or whatever.

TK70 is more versatile, i.e., you can use alkalines in an emergency or AA to D adaptor or even Li-ions. I use mine with 2 Li-ions and a dummy cell. much lighter and shorter, but not shorter than the SR92 though. using LSD NiMHs you can keep it in the car or whatever.

Of course, you might want the better quality of the SR92. SR92 has a bigger spill but less throw. Warmer tint as well. Real great anodising, i think. But price is one of the most important factors for me

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by HKJ

The problems is that alkaline cannot deliver 5 to 10 ampere, they where never designed to deliver a high current.

Thanks for the answer. HKJ!
On the turbo mode, Can I assume the current per LED is appro. 3A?
Did you use a pan for cooling the light to check runtime?
Is the automatic step down on turbo due to the time control or temperuture control?

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by candle lamp

Thanks for the answer. HKJ!
On the turbo mode, Can I assume the current per LED is appro. 3A?
Did you use a pan for cooling the light to check runtime?
Is the automatic step down on turbo due to the time control or temperuture control?

Thanks in advance.

I can answer a couple of those questions:
As it is current controlled output, the total current draw ranges between about 4.5 and 9.5 Amperes on turbo. See the turbo chart. The draw at emitter would be split equally between the three emitters.
The level step-downs are purely voltage based, nothing to do with time or temperature.

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by candle lamp

On the turbo mode, Can I assume the current per LED is appro. 3A?

Yes, the light uses about 30 to 36 watt on turbo, that is 10 to 12 watt for each led. This is enough to drive a XM-L led at 3 ampere (This requires 10 watt) and also have some driver looses at the higher current.

Originally Posted by candle lamp

Did you use a pan for cooling the light to check runtime?

I uses a fan for cooling.

Originally Posted by candle lamp

Is the automatic step down on turbo due to the time control or temperuture control?

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by samgab

I can answer a couple of those questions:
As it is current controlled output, the total current draw ranges between about 4.5 and 9.5 Amperes on turbo. See the turbo chart. The draw at emitter would be split equally between the three emitters.
The level step-downs are purely voltage based, nothing to do with time or temperature.

Originally Posted by HKJ

Yes, the light uses about 30 to 36 watt on turbo, that is 10 to 12 watt for each led. This is enough to drive a XM-L led at 3 ampere (This requires 10 watt) and also have some driver looses at the higher current.

Re: Fenix TK70 with measurements and outdoor beamshots

I've been using mine routinely for over a month now and it really delivers the lumens when I need them. Have not found anything wrong or any downside to it yet. The strap works fine for my use but will replace with a more substantial cloth strap in the future.

Re: Fenix TK70 with measurements and outdoor beamshots

Hi, I am in the process of buying a TK70, after also looking long and carefully at the SR92. As Zed888 says, as nice as the SR92 is, its a little bit difficult to justify the price. At least if the TK does get a few scratches, you wont feel quite so bad. Is 60 minutes all you can expect on a quality set of 10,000mah NiMh cells? I guess you can at least charge cells individually, occasionally to give some sort of cell balance.
Best wishes, Mike.

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by harro

Hi, I am in the process of buying a TK70, after also looking long and carefully at the SR92. As Zed888 says, as nice as the SR92 is, its a little bit difficult to justify the price. At least if the TK does get a few scratches, you wont feel quite so bad. Is 60 minutes all you can expect on a quality set of 10,000mah NiMh cells? I guess you can at least charge cells individually, occasionally to give some sort of cell balance.
Best wishes, Mike.

Yes, 60 minutes is all you can expect on Turbo between charges... But the head gets REALLY hot if left on turbo... I don't think I'd want to run it for an hour on turbo continuously without some kind of cooling.
When I did my runtime test I ran it under cold water periodically because I was worried about the heat it was getting up to.
My fears may have been unfounded, but I was concerned none-the-less.

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by harro

Hi, I am in the process of buying a TK70, after also looking long and carefully at the SR92. As Zed888 says, as nice as the SR92 is, its a little bit difficult to justify the price. At least if the TK does get a few scratches, you wont feel quite so bad. Is 60 minutes all you can expect on a quality set of 10,000mah NiMh cells? I guess you can at least charge cells individually, occasionally to give some sort of cell balance.
Best wishes, Mike.

Well, after having bought the TK, i'm not dissapointed. Huge output. Huge appetite on turbo ( about 55 mins on 10aH 'D' cells ) but there's three lower settings if 2200 lms is too much. I notice if you run constantly on turbo without forced cooling, after about 15 mins or so, it drops a level for thermal protection. Makes my mate's LLX21 look a little pale but!!
Best wishes, Mike.

Re: Fenix TK70 with measurements and outdoor beamshots

Originally Posted by joe1512

How come I don't see any of the pictures? This seems to be a common theme with CPF's even slightly older posts.

This time it must be something with your computer.
CPF does not host the pictures, it must be done by the poster, usual on some photo site that has a time limit. When the photo site removes the picture it will also disappear here.
My pictures are hosted on my own website and as long as I am running that site, the pictures will be there (This will hopefully be for many years).